It is our objective to demonstrate that the testicular capsule is capable of responding to various drugs and neurohumoral agents. In addition, we hope to demonstrate that the testicular capsule is a dynamic tissue capable of undergoing spontaneous contractions. It is our hope to associate such contractions of the testicular capsule with the function of providing a propelling action which acts to transport non-motile sperm out of the testis and into the epididymis where the sperm can then attain their motility. Our approach to the problem will begin with the development of a usable pharmacological testicular capsule isolated tissue preparation of the rat and rabbit that will be capable of recording in vitro drug effects on testicular capsular tension, as well as attempting to demonstrate spontaneous contractions of the testicular capsule. Our in vitro studies will then continue with an investigation of some of the various factors that may influence the extent of testicular capsular contractions. Our next approach will deal with the development of an adequate in vivo pharmacological preparation which can be used to measure testicular capsular contractions of the intact testis of anesthetized rabbits. This in vivo preparation of the intact testicular capsule will then be used to determine both the effect of systemically-administered drugs and environmental poisons as well as to ascertain whether the testicular capsule has any nervous innervation which might influence testicular capsular contractions. In addition, an anatomical basis for such contractions of the testicular capsule will be attempted by investigating the presence and extent of smooth muscle in the testicular capsule.